Alopecia is a syndrome of loss of hair resulting from the decrease of hairs in the anagen phase of a hair growth cycle and from the increase of hairs in the catagen phase or telogen phase of the hair growth cycle. Although the mechanism of alopecia is unclear, a lot of factors causing alopecia might be endocrine disorder, hormone unbalance, autonomic nerves disorder, circular disorder, excessive sebum due to the abnormal blood circulation, degeneration of skin due to fungi, allergy, genetic disorder, or aging.
Alopecia is one of most serious side effects in cancer that is induced by various chemotherapeutic agents. Since these chemotherapeutic agents interrupt cytokinesis, the chemotherapeutic agents will induce side effects in the tissues, where cytokinesis frequently occurs, including bone marrow, hair follicle, fingernail, toenail, skin and gastrointestinal tract. Thus, the chemotherapeutic agents induce alopecia. Most of patients (80% or above) regard alopecia as the most painful effect in their chemotherapy. The need for treating alopecia due to the chemotherapy is still strong and not fulfilled.
Alopecia occurs in two to four weeks after the treatment of chemotherapy. Hair will grow during three to six months after the chemo-treatment. The degree of alopecia depends on the types of chemotherapeutic agents, the dosage thereof and the schedule of administration. Those agents inducing serious alopecia include cyclophosphamide, doxorubicin, cisplatin, cytosine arabinoside and etoposide. The above-mentioned agents induce alopecia even if those are administrated in partial area of the skin. In other words, the chemotherapeutic agents affect the cytokinesis of the hair follicle that induces apoptosis of the follicle cells or converts the anagen phase of the follicle cells into the catagen phase.
Currently, the clinic approaches for alopecia includes applying external medicine on the hair follicle, orally administrating medicine, and hair implantation. Minoxidil and Finasteride are two kinds of medicine for growth hair that are approved by FDA. Patients with alopecia are often required to continuously administrate Minoxidil for external use and the Finasteride for internal use. In addition, Minoxidil and Finasteride may only reduce the loss of hair instead of increasing the number of hair follicles. Moreover, since Minoxidil and Finasteride have several side effects such as sexual dysfunction, hypertrichosis, and fetus defect, none of the medicines can be administrated for pregnant women. Furthermore, hair implantation may leave scars, require a long recovering period, and cost a lot due to several times of surgery.